Start a new Free Mode game. Go to a bank and take a loan.
The go to the next bank, take a loan and so on. Until you 
have too much loans. Then save as character and exit the 
game.
Start the game again and start a new Free Mode game. Load
the saved character and start the game. Now you don't have
too pay back the loans! You cane do the same thing again and
again and you still don't have too pay!

Scott Mason

To maximise space in your restruants.. The best way to cram as many people into your restruants as you can can be done like this - Firstly, find a restruant of which size you prefer, the bigger the better. Buy furniture from "Restruant Furnishings" (the 3rd best quality), but Light Marble tables ($6500 each) and for each of the tables buy four Billiard Green seats ($1500 each). Then once you have a fair amount of tables, buy stools for "Modern Living" and carefully place a chair of the corner of each table. If done correctly, you can have room for eight people, and the customers won't know the difference. This allows you to have 3000+ people in your restruant daily. Also, using the above furniture, you will receive high popularity ratings from the customers.

James

To get loads of cash: go around the various cities looking at bomb prices, when you find them cheap ($6000 or less) buy as many as possible and sell them to a dealer in another city, who will pay loads of money ($10000 or more) repeat this until you have loads of money, this also improves your underworld standing. also try: take out liabilty insurance from an expensive company, commit a crime, pay the fine imposed by the police, claim on your insurance, you should get about $100000 each time.

Knox Beasley

In character select start a game with 6 human players. Pick the one you want to play as. Let the rest of the players (except the computer player) have the most money available. Start the game in Berlin. Skip your turn. The next player will come up. Let him borrow as much money from the bank as possible. Repeat the proceduce with all the human players except yours. Transfer all the money that they got from the bank into you account. You will have a lot of money (11 million if done correctly) and the other computer player will be in debt.